The H3+ab initiopotential energy surface and its analytical representation has been re-examined to promote more accurate vibration-rotation calculations. We present here a new and accurate 78 point PNO-CI grid which predicts the minimum energy geometry to be an equilateral triangle of side,r(H-H)= 1·6525a0. and energy of -1·34188Eh. Of the analytical representations only the sixth order Simons-Parr-Finlan (SPF) and Ogilvie force fields were found to satisfy our fitting criteria, resulting in associated errors of less than 11·1 kJ mol-1. Our calculated vibrational band origins are in good agreement with those of Carney and Porter, with the differences of the lowest-lying vibration states essentially reflecting the analytical characteristics of the potential energy surfaces used.